The invention relates to system control, and more particularly, to detecting and suppressing control methods for milling tool chatter.
A ┌Machine Tool┘ used in facility manufacturing is driven by a power source, manufacturing metallic workpieces using physical, chemical, or other processes for formation. Manufacturing methods comprise milling or grinding metallic workpieces to desired shape, size, and surface precision. Manufacturing technologies for machine tools have rapidly developed, comprising high speed milling (HSC) and high speed feeding (HSF) methods.
HSC enhances metal removal rate to reduce process time and cost and result in higher surface precision. To harmonize with running efficiency of a machine tool, milling parameters can only be set within a fixed range, or the machine tool generates chatter during milling. When chatter occurs, workpieces may become unusable or damaged, and even the machine tool may experience damage. Current detecting and suppressing methods for chatter change structural features based on structural mode of a machine tool or utilize related controls.
In the Hualizhong Li and Xiaoping Li disclosure MODELING AND SIMULATION OF CHATTER IN MILLING USING A PREDICTIVE FORCE MODEL, simulating and predicting milling force degrees and chatter states creates a dynamic milling model.
In the S. K. KIM and S-Y. Lee disclosure CHATTER PREDICTION OF END MILLING IN A VERTICAL MACHINING CHATTER, a dynamic milling model is created according to geometrical characteristics of milling tools affecting milling force to predict whether chatter occurs in a vertical milling tool.
In the K. J. Lin and K. E. Routh disclosure OPTIMAL PASSIVE VIBRATION CONTROL OF CUTTING PROCESS STABILITY IN MILLING, dampening uses an optimum control method to suppress chatter, defining an objection function according to milling depth, milling width, and spindle rate to obtain optimum m, c, and k values of a dynamic structure of the damper.
In the Jingchuan Pan, Chun-Yi Su, and Yury Stepanenko disclosure MODELING AND ROBUST ADAPTIVE CONTROL OF METAL CUTTING MECHANICAL SYSTEM, a lathe tool seat uses a robust adaptive control method and regulates a feed amount of the lathe tool using an actuator to change milling thickness for chatter suppression.
As described, many other chatter suppression methods are provided. Current chatter suppression methods, however, cannot detect and suppress chatter occurring immediately, and are thus incapable of improving surface precision. Thus, an effective method for suppressing chatter is desirable.